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ARSTRACT 
The authors have developed a software for processing the SEASAT SAR data 
using a supercomputer. The supercomputers, FACOM VP-200/VP-100, are vector 
processors with maximum performance rate of 533 MFLOPS/267 MFLOPS and large 
main memory of up to 256 MB/128 MB, respectively. 
The software is designed to get the highest performance system. In order 
to reduce the CPU time, an isogeometric FFT is employed because this algorithm 
is suitable for a vector processor. The corner turning is not performed because 
2-dimensional data reside on main memory. In order to shorten the I//0 time, 
the parallel file access method is applied, which is a function of the FORTRAN77 
/%P. 
À SEASAT SAR image (90km in azimuth x 100km in range) has been processed 
in 20.18 minutes using a loosely coupled system of FACOM VP-200 and FACOM M-380, 
where FACOM M-380 is a general purpose computer. In the case that many scenes 
are continuously processed, the processing time per scene becomes 8.55 minutes.